RFID Actuated Gravel Pack Valves

ABSTRACT

A device and method that, on a command from the surface, a seat in a tubular may be moved into the bore of a tubular so that a ball of the appropriate size may be caught. The seat may also be moved out of the bore on command so that a ball of the appropriate size will not be caught by the seat.

BACKGROUND

Hydrocarbon wells, horizontal wells in particular, typically have sections of wellscreens having a perforated inner tube with an overlying screen portion. The purpose of the screen is to block the flow of particulate matter into the interior of the production tubing. Despite the wellscreen some contaminants and other particulate matter still enter the production tubing. The particulate matter usually occurs naturally or is part of the drilling and production process. As the production fluids are recovered the particulate matter is also recovered at the surface. The particulate matter causes a number of problems in that the material is usually abrasive reducing the life of any associated production equipment. By controlling and reducing the amount of particulate matter that is pumped to the surface overall production costs are reduced.

Even though the particulate matter may be too large to be produced the particulate matter may cause problems at the downhole wellscreens. As the well fluids are produced the larger particulate matter is trapped in the filter element of the wellscreens. Over the life of the well as more and more particulate matter is trapped in the filter elements the filter elements will become clogged and restrict flow of the well fluids to the surface.

A method of reducing the inflow of particulate matter before it reaches the wellscreens is to pack gravel or sand in the annular area between the wellscreen and the wellbore. Packing gravel or sand in the annulus provides the producing formation with a stabilizing force to prevent any material around the annulus from collapsing to produce particulate matter and it also provides a pre-filter to stop the flow of particulate matter before it reaches the wellscreen.

In typical gravel packing operations a screen and packer are run into the wellbore together. Once the screens and packer are properly located the packer is set so that it forms a seal between wellbore and the screen isolating the region above the packer from the region below the packer. The screen is also attached to the packer so that it hangs down in the wellbore forming an annular region around the exterior portion of the screen. The bottom of the screen is sealed so that any fluid that enters the screen should pass through the screening or filtering material. The upper end of the screen is usually referred to as the heel and the lower end of the screen is usually referred to as the toe of the well.

Typically a washpipe subassembly is put together on the surface and then run into the wellbore where it stings through the packer and then run into the screen. The run in continues until the crossover tool lands on an internal seal in the packer.

Once the crossover tool lands on internal seal in the packer a ball is pumped downhole. The ball lands on one of two seats in the crossover tool. Once the ball lands on the second seat pressure is applied from the surface across the ball and seat to shift the sleeve in the crossover tool so that fluid, typically gravel slurry, may be pumped down the well through the washpipe. When the slurry reaches the crossover tool the gravel slurry is blocked by the ball and seat that was previously landed in the crossover tool. The ball and seat causes the gravel slurry to exit the crossover tool through a port that directs all fluid flow from inside of the washpipe that is above the packer to the outside of the washpipe and screens below the packer and into the annular space created on the outside of the screen.

As the slurry travels from the heel of the well toward the toe along the outside of the screen, and alpha wave begins that deposits gravel from the heel towards the toe, all the while the transport fluid that carries the gravel drains to the inside of the screen. As the fluid drains into the interior of the screen it becomes increasingly difficult to pump the slurry down the wellbore. Once a certain portion of the screen is covered the gravel will start building back from the toe towards the heel, the beta wave, to completely pack off the screen from approximately its furthest point of deposit towards the heel. As the sand fills back towards the heel the pressure in the formation is increasing.

The crossover tool has a second port that allows fluid to flow from the interior area of the screen below the packer to an annular area around the exterior of the washpipe but above the packer.

After the annular area around the screen has been packed with gravel a second ball may be pumped down the well to land in a second ball seat in the crossover tool. After the ball has seated pressure is applied from the surface to shift the sleeve in the crossover tool a second time as well as seal off the internal the sleeve in a second location. Once the sleeve is shifted and is sealed in a second location wellbore fluid from the surface flowing through the washpipe may be directed into an internal flowpath within the crossover tool and then back into the interior of the washpipe thereby bypassing both the first and the second balls and seat. Once the fluid has been redirected to stay in the washpipe the operator may reposition the washpipe and begin to acidize or otherwise treat the wellbore.

In the current system fluid flow through the interior is limited by forcing the fluid to travel through the micro-annulus, the only path available in crossover tool. The only alternative is to reverse the washpipe and crossover tool completely out of the hole and run in with an unobstructed washpipe. The additional trip out of the hole and then back in leads to additional time and expense in completing the well.

When typical seals, as described above, are used care must be taken so that each lower seal and seat has a diameter that is smaller than the seal and seat above it. Such an inverted wedding cake arrangement helps to insure that the operator does not attempt to force a device through a seal that is too small thereby damaging the seal.

Such an arrangement may limit the diameter of the bore through the tubular. Also, typically once a device seals on a particular seat the seat cannot be reused. When several seal and seats are needed in close proximity the utility of the tool or tools may be limited.

SUMMARY OF THE INVENTION

In the new system neither a second trip into and out of the well is necessary to treat the well while greatly improved fluid flow through the interior of the casing thereby potentially allowing a larger diameter screen and consequently a larger washpipe may be used with the same technique allowing greater flow through the washpipe, even when no increase in washpipe diameter is achieved.

The fluid flow may be improved by replacing the seal in the packer and the balls and seats in the washpipe with variable diameter seats that may be operated on demand such as by pressure pulses or a radio frequency identification device.

A variable diameter seat has utility in any device where a seat diameter is a limiting factor when compared to the bore diameter and when the seat and seal are only required on demand.

One embodiment of the variable diameter seal has a seat that is a combination of several portions. When the seat is not necessary the portions may be held radially outward so that an increased diameter of the bore may be accessed, such as when a large diameter tool, dart, or ball is required to pass through. However, when the seat is required for a ball or dart to seal upon it, then, on command from the surface, the seat may move radially inward so that the various pieces combine to form at least a seat and possibly even a seal against fluid flow through the bore and past the seat.

When the operator determines that the seat is no longer necessary then the operator may send a second signal to unlock the seat and move it radially outward once again. The command from the surface may be radio, low frequency radio, pressure pulse, a fiber optic line, an electric line, or a radio frequency identification device.

Another embodiment of this invention is to utilize a collet and sleeve. The sleeve could be removed from the collet fingers so that any tool, dart, or ball, when reaching the collet fingers could pass by without interacting with the collets finger. In the potential instance where the tool, ball, or dart does interact with the collet fingers the tool would merely push the collet fingers radially outward, with a minimal resistance, and continue downhole.

Once the operator determines that the seat is required a signal may be sent for the surface to move the sleeve into position over the collet so that the fingers are moved radially inward or are at least held in a radially inward position so that the collet fingers will no longer allow an appropriately sized tool, ball, or dart to pass. Further once the appropriately sized tool, ball, or dart lands on the seat a seal across the bore may be formed.

In a further embodiment at least the seals mentioned may be constructed so that they have an open condition as described above, however, when the signal is sent from the surface to move radially inward the seats are constructed so that once they have moved radially inward they completely obstruct the bore without the need of a ball, tool, or dart landing upon the seat. Each seal forms a complete seal by itself upon a command from the surface.

Such seals may be used in many different areas. They may be used to open and close gravel pack paths or to provide seats in sliding sleeves to open and close the sliding sleeve.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 depicts a collet type radial movable seat operable from the surface in its catching condition.

FIG. 2 depicts a collet type radial movable seat operable from the surface in its released condition.

FIG. 3 depicts the collet type segmented seat in its radially unlocked condition.

FIG. 4 depicts the collet type segmented seat in its radially locked condition.

FIG. 5 is a top view of a segmented seal in the open position.

FIG. 6 is a top view of a segmented seal in the closed position.

DETAILED DESCRIPTION

FIG. 1 depicts a collet 10 in its radially locked condition in a housing 11 so that a ball, dart, or other tool, of the appropriate size, will be caught by the collet 10. To operate the collet 10 a receiver 12 will receive a signal communicated from the surface by a radio frequency identification device, a pressure pulse, or by other means known in the industry. When the receiver 12 receives the appropriate signal the receiver 12 causes the actuator 14 to move the lock 16 upwards or downwards, in this case the lock is shown in its downward position, in channel 18. In the radially locked condition the collet 10, at the collet fingers 42, has a diameter 22 that is less than the main bore diameter 20 such that a ball, dart, or tool that could pass through the main bore 24 will be caught by the collet fingers 42. The collet 10 could be attached to a sliding sleeve or other device where force needs to be applied across a ball and seat.

FIG. 2 depicts the collet 10 in its radially unlocked condition. In the radially unlocked condition the collet fingers 26 are not able to catch a ball, dart, or other tool. To change the condition of the collet 10 from the locked condition to the unlocked condition the receiver 12 receives a signal communicated from the surface by a radio frequency identification device, a pressure pulse, or by other means known in the industry. When the receiver 12 receives the appropriate signal the receiver 12 causes the actuator 14 to move the lock 16 upwards in channel 18. By moving the lock 16 upwards the collet fingers 26 are allowed to move radially outwards into channel 18. In the radially unlocked condition the collet 10, at the collet fingers 26, has a diameter 28 that is sufficient to allow a ball, dart, or tool that could pass through the main bore 24 to pass through collet 10.

FIG. 3 depicts the collet type segmented seat 40 in its radially unlocked condition. In the radially unlocked condition the segmented seat 40 is not able to catch a ball, dart, or other tool. To change the condition of the segmented seat 40 from the locked condition to the unlocked condition the receiver 42 receives a signal communicated from the surface by a radio frequency identification device, a pressure pulse, or by other means known in the industry. When the receiver 42 receives the appropriate signal the receiver 42 causes the actuator 44 to move the lock 46 upwards in channel 48. In the radially unlocked condition the segmented seat 40 has a diameter 58 that is sufficient so that a ball, dart, or tool that could pass through the main bore 56 is able to pass through segmented seat 40.

FIG. 4 depicts a segmented seat 40 in its radially locked condition. In the radially locked condition a ball, dart, or other tool, of the appropriate size, will be caught by the segments 50 of the segmented seat 40. To operate the segmented seat 40 a receiver 42 will receive a signal communicated from the surface by a radio frequency identification device, a pressure pulse, or by other means known in the industry. When the receiver 42 receives the appropriate signal, the receiver 42 causes the actuator 44 to move the lock 46 upwards or downwards. In the view depicted, the lock 46 is shown in its downward position, in channel 48. As the lock 46 moves downward, a first surface 47 on the lock 46 interacts with a second surface 49 on the segmented seat pieces 50 such that each of the plurality of segmented seat pieces 50 is forced radially inwards so that in the radially locked condition the segmented seat has a diameter 52 that is less than the main bore diameter 54 such that a ball, dart, or tool that could pass through the main bore 56 will be caught by the segmented seat 40. The segmented seat 40 could be attached to a sliding sleeve (not shown) or other device where force needs to be applied across a ball and seat.

FIG. 5 is a top view of a segmented seal 100 that is similar in operation to the seat depicted in FIG. 3. As shown in radially unlocked position the flowpath may allow fluid or slurries to pass through the main bore 116. In some instances, as shown, the main bore diameter 110 may be restricted. Upon the receiver receiving a signal from the surface an actuator may move a locking ring longitudinally with respect to the tubular housing 112 to force each segment 114 of the segmented seal 100 radially inward.

FIG. 6 is again a top view of a segmented seal 100 that is similar in segments 114 operation to the seat depicted in FIG. 3, however, in the view shown the segments 114 of the segmented seal 100 have been moved radially inward to block all flow through the main bore 116. The lock 118 will generally fill the annular area between the interior of the tubular housing 112 and a radially outward surface of the segments 114. With the lock in position between the tubular housing 112 and the segments 114 the segments 114 are prevented from unlocking and allowing fluid or slurry to pass through the main bore 116. The sealing surfaces between each of the segments 114 may be a metal to metal seal, an elastomeric seal, or any other seal known in the industry. In certain instances a less than perfect seal may be acceptable.

While the embodiments are described with reference to various implementations and exploitations, it will be understood that these embodiments are illustrative and that the scope of the inventive subject matter is not limited to them. Many variations, modifications, additions and improvements are possible.

Plural instances may be provided for components, operations or structures described herein as a single instance. In general, structures and functionality presented as separate components in the exemplary configurations may be implemented as a combined structure or component. Similarly, structures and functionality presented as a single component may be implemented as separate components. These and other variations, modifications, additions, and improvements may fall within the scope of the inventive subject matter. 

1-20. (canceled)
 21. A downhole releasable valve seat, comprising: a housing having an interior; a valve seat located in the interior, the valve seat having at least two segments, the segments having a first position and a second position; and a receiver receiving a signal and moving the segments, upon receipt of the signal, between the first position and the second position.
 22. The seat of claim 21, wherein the segments move radially between the first position and the second position.
 23. The seat of claim 21, wherein the segments in the first position allow a plug to pass through the interior; and wherein the segments in the second position catch the plug.
 24. The seat of claim 23, wherein the segments in the second position form a seal with the caught plug.
 25. The seat of claim 21, wherein the receiver actuates a lock, the lock moving the segments between the first position and the second position.
 26. The seat of claim 21, wherein the receiver receives the signal communicated by a radio frequency identification device.
 27. The seat of claim 21, wherein the receiver receives the signal communicated by a pressure pulse.
 28. A downhole releasable valve seat, comprising: a housing having an interior; a valve seat located in the interior, the valve seat including a collet having at least two fingers, the fingers having a first position and a second position; and a receiver receiving a signal and moving, upon receipt of the signal, the fingers between the first position and the second position.
 29. The seat of claim 28, wherein the fingers move radially between the first position and the second position.
 30. The seat of claim 28, wherein the fingers in the first position allow a plug to pass through the interior; and wherein the fingers in the second position catch the plug.
 31. The seat of claim 30, wherein the fingers in the second position form a seal with the caught plug.
 32. The seat of claim 28, wherein the receiver actuates a lock, the lock moving the fingers between the first position and the second position.
 33. The seat of claim 28, wherein the receiver receives the signal communicated by a radio frequency identification device.
 34. The seat of claim 28, wherein the receiver receives the signal communicated by a pressure pulse.
 35. A downhole valve, comprising: a housing having an interior; a valve located in the interior, the valve having at least two segments, the segments having a first position and a second position; and a receiver receiving a signal and moving, upon receipt of the signal, the segments between the first position and the second position.
 36. The valve of claim 35, wherein the segments move radially between the first position and the second position.
 37. The valve of claim 35, wherein the segments in the first position allow fluid to pass through the interior; and wherein the segments in the second position block fluid flow through the interior.
 38. The valve of claim 37, wherein the segments in the second position form a seal.
 39. The valve of claim 35, wherein the receiver actuates a lock, the lock moving the segments between the first position and the second position.
 40. The valve of claim 35, wherein the receiver receives the signal communicated by a radio frequency identification device.
 41. The valve of claim 35, wherein the receiver receives the signal communicated by a pressure pulse. 